In the long term evolution-advanced (Long Term Evolution-Advanced, LTE-A) R11 version, different carriers (including a primary carrier, and the rest is a secondary carrier) supported by a user equipment (User Equipment, UE) are allowed to have different timing advance (Timing Advance, TA) values. The UE may obtain, according to a TA value of a carrier, time advance amount required for sending an uplink channel through the carrier, so that the time when the uplink channel sent through the carrier arrives at a base station (Evolved Node B, ENB) is consistent with a preset time of the ENB, thereby completing uplink transmission synchronization of the UE, and further the UE may be scheduled by the ENB for uplink transmission.
In an actual application, carriers may be grouped into different timing advance groups (Timing Advance Group, TAG) according to different TA values of the carriers, and TA values of carriers in each TAG are the same. Because TA values of carriers of different TAGs are different, when the UE sends an uplink channel through carrier 1 and carrier 2 that have different TAGs, partial overlapping may occur between subframe n of carrier 1 and adjacent subframe n+1 of carrier 2 as shown in FIG. 1. In the overlapped area (which is about one symbol), there may occur that uplink transmission power of the UE exceeds the maximum transmission power of the UE, which results in a power limitation, or uplink transmission power of the UE may reach an interference level, which results in an interference limitation.